From the trailer it looks like Smith has taken over the entire world, but if Neo defeats the original, who is now as powerful as Neo himself, everyone will be set free. I think Revolutions will mostly be about Smith, because I remember hearing in an interview with Keanu Reeves: "The first film is about birth, the second about life, the third about death". During the trailer at the exact moment the Oracle says "I see death", we see Agent Smith. If he does represent death, then the film will probably be mostly about him.